1. Field of the Invention
The present invention relates to a door operator, in particular a door closer for operating a door.
2. Related Art
Door operators are understood to be in particular door closers, servo-assisted door closers and door drives. In door closers, an energy accumulator is usually pre-loaded by manually actuating the door leaf. The door can be closed again without manual actuation, by discharging the energy accumulator. The door closers are either attached directly to the door leaf, to a door transom or to a wall. With an attachment to the door leaf, an arm assembly is attached to the output shaft of the door closer. It is via this arm assembly that the force is transferred onto the wall, respectively onto the transom. When mounting the door closer to the transom or to the wall, the force is transferred onto the door leaf via the arm assembly. As an alternative, it is likewise possible to connect the output shaft coaxially to the axis of rotation of the door. With known door operators with a cam drive, the installation of the cam with the output shaft is problematic in the limited constructional space between the opening piston and the damping piston, respectively the closing piston.